Electrical Resistivity Tomography
Electrical resistivity tomography (ERT) is a geophysical technique for imaging sub-surface variation of resistivity value from 2D/3D electrical resistivity survey made at surface or borehole. The properties that affect the resistivity of soil or bedrock include porosity, water content, composition (clay mineral and metal content), the salinity of the pore water, and grain size distribution. During resistivity surveys, artificial-ly-generated, near direct current (DC) between current electrodes are injected into the ground and electric potential between two or more pairs of receiver electrodes are measured simultaneously. 2D/3D Inverse modeling is then performed to obtain a sub-surface model of the surveyed site. Therefore, the resistivity tomography survey is ideally suited to investigate the lateral and vertical change of subsurface resistivity and also delineate three-dimensional resistivity anomalies.
Depending on the client's need, SDI uses state of the art multi-channel resistivity equipment to acquire data from depths as great as 300 feet. Finite element inversion processing software is adapted to perform bore, 2D or 3D inversion to produce the best result for any situation. SDI personals have extensive experience in conducting terrestrial and marine resistivity survey for all filed conditions and interpreting data for a variety of applications. We will provide you with an accurate assessment of your requirement to design a survey at a particular site.